Proceedings of the 4th International Congress on Oxygen Radicals will be organized for publication in a book that will serve as a didactic and source book to enhance research and applications of free radial processes in chemistry, foods, biology, pharmacology, medicine in general, and cancer therapy in particular. NIH support is requested for temporary personnel to assist in putting such a book together. The Congress will deal with the phenomena associated with highly reactive oxygen species (hydroxy, peroxy, alkoxy, aroxy, and superoxide radicals, as well as singlet oxygen) and their peroxidation products (hydrogen peroxide, hydroperoxides, peroxides, and epoxides). The kinetics, energetics, and mechanistic aspects of the reactions of these species and the interrelationship of oxygen radicals (or any other free radicals) and peroxidized products will be emphasized. Special attention will be given to the mechanisms of the generation of free radicals and peroxy products in biosystems and the adverse effects of these radicals and products in humans. The program will span the continuum from the simple chemistry of model systems to the complex biochemistry, physiology, and clinical medicine.